如何使用SharedPreference以以下格式保存和获取Android中的Hashmap
HashMap<String, List<String>> mChildMap = new HashMap<>();
HashMap<String, List<String>> mChildMap = new HashMap<>();
插入HashMap到SharedPreference的函数
private void insertToSP(HashMap<String, List<String>> jsonMap) {
String jsonString = new Gson().toJson(jsonMap);
SharedPreferences sharedPreferences = getSharedPreferences("HashMap", MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString("map", jsonString);
editor.apply();
}
从SharedPreference中读取hashMap的函数
private HashMap<String, List<String>> readFromSP(){
SharedPreferences sharedPreferences = getSharedPreferences("HashMap", MODE_PRIVATE);
String defValue = new Gson().toJson(new HashMap<String, List<String>>());
String json=sharedPreferences.getString("map",defValue);
TypeToken<HashMap<String,List<String>>> token = new TypeToken<HashMap<String,List<String>>>() {};
HashMap<String,List<String>> retrievedMap=new Gson().fromJson(json,token.getType());
return retrievedMap;
}
implementation 'com.google.code.gson:gson:2.6.2'
String converted = new Gson().toJson(myMap);
SharedPreferences sharedPreferences = getSharedPreferences("mySharedName", Context.MODE_PRIVATE);
sharedPreferences.edit().putString("key",converted).commit();